CD274 and melanoma: While sampling tumors for PD-L1 expression, tumor mutational burden (TMB) and inflammation have identified associations with response to PD-1 blockade therapy in multiple cancers including melanoma, renal cell carcinoma (RCC) has remained an outlier with respect to their utility.1 RCC is consistently and highly inflamed but has a lower TMB than most types of PD-1 responsive tumors.2 For RCC, transcription-based tumor subtypes have proved to be indicators of response, for both tyrosine kinase inhibitors (TKIs) and immunotherapies.3 4 A common biomarker for these tumors is lacking.